Psion manufactured handheld computers, but not only
palmtops. They made few models of data collectors which allowed to
collect data and even print results on the go. HC-120 was the second
model of HC line, with EPOC system. It has 2 expansion slots for I/O
modules and 2 slots for memory cards, usually battery-backed RAM disks.
Rechargeable battery pack allowed to work without connecting to power
source for at least few hours.

Manufacturer

Psion

Origin

UK

Year of unit

1993?

Year of introduction

1992

Type

Data collector

This unit is in fact a full-featured
computer running EPOC operating system without GUI. It has a
full alphanumeric keyboard and backlit (quite poor) LCD. After
starting, it may load software from RAM
disk. If no software is present, it runs EPOC command-line
system from ROM allowing to prepare (format) RAM disk or manage
files.

I've got both of my Psion's from electronic junk, they
were used by gas company. Meter readers used Psion handhelds to enter data and print
confirmations of read. Small, portable thermal printer was connected using RS232 port, and
it was Able Systems printer. Unfortunately my printer doesn't work and I
don't have a cable for it.

Psion Workabout MX

Psion manufactured handheld computers, but not only
palmtops. They made few models of data collectors which allowed to
collect data and even print results on the go.
Workabout MX is another computer for collecting data. This model has 2
serial ports, IR port and applications in ROM. It can still be expanded
by battery-kept RAM disk cards.

Manufacturer

Psion

Origin

UK

Year of unit

1996?

Year of introduction

1995?

Type

Data collector

This unit is in fact a full-featured
computer running EPOC operating system with GUI and some
programs. It has a full alphanumeric keyboard and LED backlit
LCD. After starting with empty RAM disks, is may load software
from RAM disk. If no software is present, it runs system menu
from which user can run spreadsheet, communications program, set
of demos, command prompt or configuration. Unlike HC, it has no
expansion I/O modules, but only RAM cards. HC expansion module
can be installed only in dock.
MX batteries can be charged in a dock too. MX itself has no
charger connectors other than dock connector.

I've got both of my Psion's from electronics junk, but it
was used by gas company. Meter readers used it to enter data and print
confirmations of read. Printer was connected using RS232 port, and
it was Able Systems printer. Unfortunately my printer doesn't work and I
don't have a cable for it.

Software for PC and manuals:

PsiWin - software for management and transfer between PC and
Psion can be downloaded from
this page.

In Psion site, their IDE to make
programs for Psion handhelds was available if user registered as
developer, but later, for a short time, no registration was
needed. As Motorola bought Psion, they said "go f... yourself"
and the name of IDE is not even visible in their search engine.